Use of a subcutaneous ureteral bypass device for treatment of bilateral proximal ureteral injury in a 9-month-old cat

Analysis of lower urinary tract signs and bacteriuria in cats with subcutaneous ureteral bypass systems

Objectives

Distinguishing bacterial cystitis from subclinical bacteriuria is necessary for feline treatment protocols and antimicrobial stewardship. This can be challenging in cats with subcutaneous ureteral bypass (SUB) systems because they may present with lower urinary tract signs without bacteriuria. We investigated the relationship between positive urine culture and lower urinary tract signs in cats with SUBs, including factors associated with each.

Methods

Clinical records were retrospectively reviewed to identify cats presenting with ureteral obstruction that underwent placement of a SUB device(s). The relationship between a positive urine culture and lower urinary tract signs was determined by chi-squared analysis. Univariable and multivariable logistic regression models were performed to identify factors associated with positive urine cultures and lower urinary tract signs.

Results

Two hundred and thirty visits were recorded for 61 cats, with 36 of 230 (16%) positive cultures in 21 of 61 (34%) cats. Lower urinary tract signs were documented at 97 of 230 (42%) visits, with 37 of 61 (61%) cats demonstrating lower urinary tract signs at some point. No relationship was found between culture results and lower urinary tract signs. Risk factors for a positive culture were higher urine pH, higher urine white blood cells and the presence of bacteriuria on microscopy. Risk factors for lower urinary tract signs were younger age and being a purebred cat (vs. non-purebred).

Conclusions

A high proportion of cats with SUBs exhibited sterile lower urinary tract signs, making differentiation between bacterial cystitis and subclinical bacteriuria difficult. This highlights the need for clearer guidelines on when to treat bacteriuria in cats with SUBs.

Feline ureteral rupture with para-ureteral urinomas following blunt trauma: clinical presentation and long-term outcome after treatment by urinary diversion for five cases from 2012 to 2019

CASE HISTORY

Medical records were reviewed for cats that underwent surgical treatment of traumatic ureteral rupture (TUR) using urinary diversion procedures between 2012 and 2019.

CLINICAL FINDINGS AND TREATMENT

Five cats had presented with injuries associated with road traffic accidents. These included three cats with abdominal hernias that required surgical management. At a median of 15 days after the accident, cats represented with lethargy, the presence of an abdominal mass or with lower urinary tract symptoms and in all cats contrast diagnostic imaging showed proximal unilateral TUR with associated para-ureteral urinoma. Four cats received subcutaneous ureteral bypass (SUB) device placement and one had ureteral anastomosis over a stent. Unilateral cyst-like retroperitoneal fluid consistent with para-ureteral urinoma was observed in all cats and a diffuse retroperitoneal haematoma was noticed in four cats. No immediate major complications occurred, and all cats had post-operative serum creatinine concentration within the reference interval. The cat that had received a ureteral stent subsequently required placement of a SUB following stent encrustation 15 months after surgery. Median follow-up time was 34 (min 28, max 58) months and renal function was normal in all cats at the last follow-up.

CLINICAL RELEVANCE

Urinary diversion procedures provided long-term stable renal function following proximal TUR in these five cats. Delayed, subtle non-specific clinical signs subsequent to high-energy blunt trauma causing abdominal hernia and associated diffuse retroperitoneal haematoma, should raise suspicion of TUR.

ABBREVIATIONS

AFAST: Abdominal focused assessment with sonography for trauma; SUB: Subcutaneous ureteral bypass; TUR: Traumatic ureteral rupture.

Subcutaneous ureteral bypass device placement in 81 cats with benign ureteral obstruction (2013-2018)

Background

Benign ureteral obstructions (BUOs) present a therapeutic challenge in cats.

Hypothesis/Objectives

The purpose of this study was to determine the outcome and complications associated with placement of subcutaneous ureteral bypass (SUB) device in cats.

Animals

Eighty‐one client‐owned cats (117 kidneys) with BUO treated by placement of a SUB.

Methods

Retrospective study. Medical records of cats with BUO and treated by SUB device placement between 2013 and 2018 were reviewed. Outcome and complications were documented.

Results

Hospital discharge rate was 94% (76/81). Serum creatinine on admission and at the time of discharge was 5.3 mg/dL (range, 1.2 to >15 mg/dL) and 2.1 mg/dL (range, 1.1‐12.5 mg/dL), respectively. Luminal obstructions were documented in 17% (18/109) of the SUB devices of 16 cats discharged from the hospital. Infection was documented in 26% (20/76) of discharged cats. Kink of the device was documented in 10% (12/117) of devices. Time to luminal obstruction and kink were 204 days (range, 21‐1678 days) and 58 days (range, 2‐601 days), respectively. Fourteen of 81 (17%) cats required a revision surgery in order to restore patency of the device. At the time of writing, 53% (43/81) of cats were alive, with a mean survival time of 821 days (range, 1‐2170 days) after surgery. Of those that died, 52% (20/38) died of urinary related causes.

Conclusion and Clinical Importance

This study suggests that SUB device placement is associated with good outcomes and could be considered for the treatment of BUO in cats.